JPH05171895A - Construction method of double way tunnel body - Google Patents

Abstract

PURPOSE:To construct safely and easily a double way tunnel body in short period of time by a cutting method. CONSTITUTION:In a front view, approximately T-shaped right and left symmetrical base slabs 4 consisting of the wall slab 5 and the top slab 6 are erected to the foundation 1 placed to the ground G, and side slabs 9 are built between the side end of the top slab 6 and the foundation 2 in a state to set its own equilibrium W on a vertical line L passing through the ground surface 9b against the foundation 2 to connect with the top slab 6. An approximately one archshaped ring 10 having empties T1 inside the tunnel both sides of the base slabs 4 is assembled. A process mentioned above is one cycle, and the cycle is repeated to connect the ring 10 subsequently in a tunnel constructional direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the construction of a so-called multi-way tunnel body, which is suitable for constructing a so-called multi-way tunnel body having two or more insides of the tunnel, especially by an excavation method. Regarding the method.

[0002]

2. Description of the Related Art The above-mentioned excavation method is a method in which underground excavation is performed under the surface of the earth to construct a tunnel structure in the inner space, and then backfilling is performed to form a tunnel.

[0003]

There is no suitable method for constructing a so-called multi-way tunnel body having two or more insides of a tunnel safely, easily and in a short time by using this excavation method. is the current situation.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and as a first aspect, a bilaterally symmetrical base plate having a substantially T-shape in a front view, which includes a wall plate and a top plate, is grounded. Standing on the vertical slab and setting the center of gravity on the vertical line that passes through the ground contact surface with respect to the ground between the side end surface of the top plate and the ground, the side plate is erected. One cycle consists of assembling one substantially arched ring that has a tunnel inner space on both sides of the base plate by connecting it to the plate, and this cycle is repeated to connect the rings sequentially in the tunnel building direction. It has a feature.

Further, the second aspect is characterized in that the base plate and the side plate are joined and connected to each other in a state of being relatively displaced with respect to the tunnel building direction.

[0006]

According to the method of constructing the double-way tunnel body of the present invention,
Looking at one ring, the base plate is symmetrical and balanced, and the side plate is also in a well-balanced state because its center of gravity is set on the vertical line that passes through the ground contact surface with the ground. The loads do not bear each other and all reach the ground. In addition, one ring has a three-point support structure in which a triangle is formed by an upright point A with respect to the ground of the base plate, a joining point B between the base plate and the side plate, and an upright point C with respect to the ground of the side plate. It is a complex of. Further, the force of the base plate in the direction of rotation of the joint B about the standing point A and the force of the side plate in the direction of rotation of the joint B cancel each other out.

Therefore, a structure having an extremely balanced structure, and the stress applied to the base plate and the side plate is only the load and earth pressure of itself, and a structure having a very large proof stress can be obtained. Further, since the base plate and the side plate are well balanced in the installed state, it is possible to safely and easily perform the connection work between the two, and thus the construction period can be shortened.

When the base plate and the side plate are joined and connected to each other in a state of being relatively displaced with respect to the tunnel building direction, the load of the side plate is received by the existing ring. The side plate can be installed safely.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the method of the present invention will be described below in order with reference to the drawings. FIG. 1 is a front view of a tunnel body T being constructed according to the embodiment, and FIG. 2 is a top view thereof.

In FIG. 1, G is a horizontal ground on the inner bottom of the ground formed by underground excavation under the ground surface. First, on this ground G, the central and left and right foundations extending along the tunnel construction direction are provided. 1 and 2 are respectively formed by pouring concrete, and further, grooves 1a and 2a extending along the tunnel building direction are formed in each foundation 1 and 2. The groove 1a of the center base 1 is formed in a rectangular shape in cross section, and the grooves 2a of the left and right bases 2 are formed in a slant so that the outer inner surface of the groove 2a extends upward. Next, the mortar 3 is appropriately filled in the bottom of each groove 1a, 2a with the horizontal upper surface at the same level.

Next, a base plate 4, which is substantially T-shaped in a front view and is symmetrical, is erected on the central foundation 1. The base plate 4 comprises a concrete wall plate 5 and a top plate 6, and first, one wall plate 5 is set upright with respect to the ground G. This wall slab 5
It has a rectangular cross section and an umbrella-shaped bulging portion 5a at the upper end, a recess 5b is formed on the upper surface of the bulging portion 5a, and a through hole 5c through which a person can pass is formed below. ..

In order to stand this wall slab 5 on the foundation 1, the lower end of the wall slab 5 is fitted in the center along the groove 1a of the foundation 1, and the reaction force bolts 7 preliminarily screwed into the lower end from the left and right are removed. And press it against the inner surface of the groove 1a,
Further, a stay 8 is stretched between the portion immediately below the bulging portion 5a and the left and right foundations 2. The stay 8 has a variable length via a turnbuckle 8a, and the right and left lengths thereof are adjusted to be the same so that the wall slab 5 is erected vertically to the ground G. The base plate 5 is bilaterally symmetric, and since the wall plate 5 is vertically installed on the horizontal ground G and the top plate 6 is horizontal, it is in a balanced state in which it does not tilt to the left or right. However, the posture is actually held by the stay 8.

In the same manner as described above, another wall slab 5 is erected and connected to each other in accordance with the existing wall slab 5. This connection is performed by bolting joint fittings provided on the joint surface.

Next, one top plate 6 is placed on the bulging portion 5a of the two wall slabs 5 standing upright. The top plate 6 has a symmetrical rectangular shape in which a recess 6a is formed on the lower surface so as to fit the bulging portion 5a, and the width of the top plate 6 is the same as that of the wall plate 5. The top slab 6 is placed over the bulging portions 5a of the two wall slabs 5 at the center thereof, that is, with the width ½ offset in the tunnel building direction with respect to the first wall slab 5 standing upright. Then, the top plate 6 is fixed to the bulging portion 5a. This fixing is performed by screwing a bolt, which is passed through the top plate 6 from a recess 6b formed on the top surface of the top plate 6, into an insert fitting (not shown) which is embedded in the bulging portion 5a in advance and fastened.

As described above, the top plate 6 is placed on the two wall plates 5.
The two are integrated by mounting and fixing them, and the base plate 4 is erected on the ground G.

Thereafter, as shown in FIG. 2, on the bulging portion 5a of the wall slab 5 protruding toward the front side in the tunnel building direction with respect to the top slab 6, a half width of the top slab 6 is provided. Then, the top plate 6A (end top plate) is mounted and similarly fixed to the bulging portion 5a, joined to the top plate 6 and connected, and the ends are aligned. The top plates 6 and 6A are connected to each other by bolting joint fittings embedded in the joint surface.

Next, the side plates 9 are bridged between the left and right side end faces of the first top plate 6 and the end top plate 6A and the grooves 2a of the left and right foundations 2, respectively. Is connected to the top plates 6 and 6A.

The side slab 9 is arcuate and has the same width as the wall slab 5 and the top slab 6, and the inside of the leg 9a is formed in a vertical plane.

In order to bridge the side plate 9 between the top plates 6 and 6A and the foundation 2, the leg 9a is guided along the groove 2a of the foundation 2 with the convex surface facing outward. While being fitted in the center, the reaction force bolt 7 preliminarily screwed into the lower end portion from the left-right direction is rotated in the pulling direction and pressed against the inner side surface of the groove 2a, and the joining surface on the top side is joined to the top plates 6 and 6A. Match to the surface. In this state, the center of gravity W of the side plate 9 is set on the vertical line L passing through the width t of the ground contact surface 9b of the leg 9a with respect to the foundation 2. As a result, the side plate 9 is in a balanced state in which it is erected on the foundation 2 and is not inclined to the left or right.

After this, the left and right side plates 9 are connected to the top plates 6 and 6A. This connection is performed by bolting joint fittings embedded in the joint surfaces of each other.

As described above, the base plate 4 composed of the wall plate 5 and the top plate 6, the end top plates 6A, and the left and right side plates 9 are used to form a single hollow space T1 on both sides of the base plate 4. This means that the arch-shaped ring 10 has been assembled. Then, in this state, the PC wire 11 is passed through a PC hole (not shown) formed in the tops of the top plates 6 and 6A and the left and right side plates 9 so as to be continuous in the left-right direction in advance, and the ring 10 is formed. On top of
Introduce prestress in the left-right direction.

Next, the third base plate 4 is erected next to the existing second base plate 4 and the two are combined and connected to each other. A new top plate 6 is laid over and fixed to each of the bulging portions 5a. After that, the new left and right side walls 9 are the same as the above except that the first end plate 6A is removed. The second slab 6 is bridged over both side surfaces and the left and right foundations 2, and the side slabs 9 are joined and connected to the both top slabs 6 and the existing left and right side slabs 9, respectively. As a result, the substantially arched ring 10 similar to the above is assembled by the base plate 4, the top plate 6, and the left and right side plates 9, and the ring 10 is installed on the existing ring 10.
Will be linked to.

As described above, the base plate 4 is replaced with the existing base plate 4
Are erected next to each other and connected to each other, and the top slab 6 is placed over the bulging portions 5a of the wall slab 5 of the base plate 4 and fixed to the respective bulging portions 5a. Between the two side plates of the two existing top plates 6 and the left and right foundations 2, and these side plates 9 are attached to both the top plates 6 and the existing ring 10.
The steps of joining and connecting to the left and right side plates 9 respectively to construct one ring 10 and joining and joining to the existing ring 10 are repeated, and the rings 10 are sequentially coupled in the tunnel building direction. In Figure 2, (1) and (2)
(3) and (4) show the assembly order.

The transfer of the wall slab 5, the top slab 6, and the side slab 9 and the posture control are performed by suspending them with a wire 14 by a crane 13.

In the state where the ring 10 is assembled and connected in a predetermined work area, the end portion of the base plate 4 projects from the left and right side plates 9 by a half width. Mount the half-width edge side plate of plate 9.

As described above, the tunnel wall T having the two tunnel inner spaces T1 is formed by connecting the plurality of rings 10.
After building the ground on the ground G, the grooves 1a of the foundations 1 and 2,
After 2a is hardened and filled with mortar, the outside of the tunnel body T is backfilled with earth and sand, and the ground G in the tunnel inner space T1 is paved to finally obtain a tunnel. When the earth and sand are backfilled, especially when the earth pressure of the earth and sand acts on the lower ends of the left and right side plates 9 at the initial stage and the upper ends are easily subjected to the force to open left and right, the foundations 1 and 2 are reinforced in advance. It is advisable to drive the pile (indicated by reference numeral 12 in FIG. 1) or to strike the piles simultaneously when placing the foundations 1 and 2.

According to the tunnel construction method of the above embodiment, when one ring 10 is seen, the base plate 4 is balanced symmetrically, and the side plate 9 also has its center of gravity W whose leg is relative to the foundation 2. Since they are set on the vertical line L passing through the width t of the ground contact surface 9b of 9a, they are in a balanced state as well, and their loads reach the ground G without bearing each other. Further, as shown in FIG. 3, one ring 10 has a standing point A with respect to the ground G of the base plate 4, a joining point B between the top plate 6 and the side plate 9, and a standing point with respect to the ground G of the side plate 9. It is a composite of a three-point support structure in which a triangle is formed by the set point C. Further, the force in the direction of rotation of the joint point B of the base plate 4 about the standing point A (arrow A) and the force in the direction of rotation of the joint point B of the side plate 9 (arrow C) are mutually They will cancel each other out. In addition,
The arrow P in FIG. 3 is the direction of the prestressing compressive force introduced at the top of the ring 10.

Therefore, the structure is extremely balanced, and the stress applied to the base plate 4 and the side plate 9 is only the load and earth pressure of the base plate 4 and the structure has a very large proof stress. Further, since the base plate 4 and the side plate 9 are balanced in the installed state, it is possible to safely and easily perform a connecting work between the two.
Therefore, the construction period can be shortened.

Further, since the base plate 4 and the side plate 9 are joined while shifting the width of the base plate 4 by ½ in the tunnel building direction, the side plate 9 is already installed when the second and subsequent rings 10 are assembled. Even if a slight impact is applied when joining to the plate 6, the existing side plate 9 on the opposite side will be received via the existing top plate 6, so that the side plate 9 can be installed more safely. It can be carried out. In FIG. 2, for example, when the side plate 9 of (17) is installed, the side plate 9 of (14) receives the impact through the top plate 6 of (12).

The first two wall slabs 5 of the base plate 4 need to be supported by the stays 8, but after that, since they are connected to the base plate 4 of the existing ring, the stays 8 are used. Since it does not need to be supported and the side plate 9 does not have to be particularly supported, it does not take much time for installation, which also shortens the construction period.

The above embodiment is a method of constructing a tunnel having one base plate 4 and two tunnel inner spaces T1 on both sides thereof. By applying this, a plurality of base plates 4 can be formed.
Are arranged in the left-right direction to connect the top plates 6 to each other, and the left and right side plates 9 are joined and connected to the side end faces of the top plates 6 of the base plates 4 on both sides to have three or more tunnel inner spaces T1. It is also possible to build a tunnel.

[0032]

As described above, according to the method for constructing a multi-way tunnel body of the present invention, since the base plate and the side plate are balanced in the installed state, they can be connected safely and easily. The work can be performed, and the construction period can be shortened. The tunnel body becomes a well-balanced structure as a structure, and the stress applied to the base plate and the side plate is due to its own load and earth pressure. Therefore, it is possible to obtain an effect that a structure having a very large proof stress can be obtained.

[Brief description of drawings]

FIG. 1 is a front view of a tunnel body under construction according to an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a schematic front view of a ring.

[Explanation of symbols]

 4 Base plate 5 Wall plate 6 Top plate 9 Side plate 9b Ground plane 10 Ring G Ground L Vertical line T Tunnel body T1 Tunnel inner space W Center of gravity

Claims (2)

[Claims] 1. A bilaterally symmetrical base plate having a substantially T-shape in a front view, which is composed of a wall plate and a top plate, is erected on the ground, and the center of gravity of the base plate is placed between the side end surface of the top plate and the ground. One substantially arch-shaped ring with tunnel inner space on both sides of the base plate by straddling the side plate with the vertical plate passing through the ground plane against the ground and connecting this side plate to the top plate. The method for constructing a multi-way tunnel body is characterized in that assembling is defined as one cycle, and this cycle is repeated to sequentially connect the rings in the tunnel building direction. 2. The method for constructing a multi-way tunnel body according to claim 1, wherein the base plate and the side plate are joined and connected to each other in a state of being relatively displaced with respect to a tunnel building direction. ..